1. Field of the Invention
The present invention relates to a receptacle terminal consisting of an electrical contact barrel and a resilient contact tongue arranged in the electrical contact barrel for receiving a pin terminal with a reliable contact force.
2. Related Art
A conventional receptacle terminal has a resilient contact tongue integrally formed with the terminal for contacting a side surface of an associated pin terminal. To increase the contacting force against the pin terminal, there have been proposed various types of receptacle terminals each accommodating a resilient contact tongue with a larger resiliency in an electrical contact barrel of the receptacle terminal.
FIG. 5 shows one of these receptacle terminals. The receptacle terminal has a base plate 13 formed with an electrical cable crimping barrel 12 at a rear portion thereof. The base plate 13 is also formed with an electrical contact barrel 11 for receiving a pin terminal (not shown) at a fore portion thereof. The electrical contact barrel 11 accommodates a curbed resilient contact tongue 17 to resiliently contact the pin terminal. The electrical contact barrel 11 has a pair of side walls 14 raised from the base plate 13 and also has a pair of top walls 15 each formed by inwardly bending each side wall, so that the electrical contact barrel 11 is defined. The resilient contact tongue 17 is provided with a pair of fore end tabs 18 each projecting laterally from the resilient contact tongue 17 at each side thereof. Each tab 18 is inserted into one of a pair of insertion openings 16 each formed in each side wall 14 of the electrical barrel 11. Thereby, the resilient contact tongue 17 is retained in the electrical contact barrel 11 and can resiliently contact the pin terminal.
In the constitution shown in FIG. 5, the resilient contact tongue 17 has the tabs 18 at the fore end thereof to be inserted in the insertion openings 16. This causes a contact point (a bend peak) of the resilient contact tongue 17 to be positioned backward by the length of the tab, so that the associated pin terminal must have a pin having a longer length, which is disadvantageous for downsizing of a connector accommodating the receptacle terminal.
Therefore, the applicant of this patent application has proposed another receptacle terminal shown in Japanese Patent Application Laid-open No. 64-10589. This receptacle terminal, as illustrated in FIG. 6, has a resilient contact tongue 17 formed with a pair of tabs 18 each projecting from each side end of the resilient contact tongue 17. Each tab 18 is engagedly supported by an insertion opening 16 of each side wall 14 of an electrical contact barrel 11 constituting the receptacle terminal.
The receptacle terminal shown in FIG. 6 requires a clearance between the tab 18 and the periphery of the insertion opening 16 so that the resilient contact tongue 17 moves smoothly. In a state in which an associated pin terminal is not inserted, the resilient contact tongue 17 is normally positioned as illustrated in FIG. 7. However, in a state in which a pin terminal 21 is inserted, the resilient contact tongue 17 moves in the insertion direction of the pin terminal as illustrated in FIG. 8. Thereby, the tab 18 is abutting against a peripheral edge 19 of the insertion opening 16, preventing a free resilient movement of the resilient contact tongue 17. This causes a larger force for the pin terminal 21 to be inserted into the receptacle terminal.